Synthesis, Morphology, and Field-Effect Transistor Characteristics of Crystalline Diblock Copolymers Consisted of Poly(3-hexylthiophene) and Syndiotactic Polypropylene

Abstract

We report the synthesis, morphology, and the field effect transistor (FET) characteristics of the crystalline diblock copolymers of poly(3-hexylthiophene) and syndiotactic polypropylene (P3HT-b-sPP). Four diblock copolymers with various sPP block lengths, P3HT 16K -b-sPP 3K (P1), P3HT 16K -b-sPP 6K (P2), P3HT 16K -b-sPP 9K (P3), and P3HT 16K -b-sPP 14K (P4), were prepared by the click coupling of N 3 -capped sPP and ethynyl-capped P3HT. The stereoregular crystalline block sPP developed different types of molecular stacking structures and led the P3HT domains to pack lamellar edge-on structure with improved charge transporting characteristics, as evidenced by the grazing incidence wideangle X-ray scattering (GIWAXS), atomic force microscopy (AFM), and transmission electron microscopy (TEM). The FET hole mobilities of P1−P3 thin films were 4.15 × 10 −3 , 4.16 × 10 −2 , and 3.95 × 10 −3 cm 2 V −1 s −1 , respectively, which were up to 1 order of magnitude higher than that of the parent P3HT thin film (1.43 × 10 −3 cm 2 V −1 s −1 ). The crystalline-stereoregular crystalline diblock P3HT-b-sPP demonstrates that using the lattice matching concept could well clarify the molecular stacking structure of conjugated polymer segments in order to further improve the performance of organic electron devices.

Donor–Acceptor Poly(3‐hexylthiophene)‐block‐Pendent Poly(isoindigo) with Dual Roles of Charge Transporting and Storage Layer for High‐Performance Transistor‐Type Memory Applications

“…With the increase of Piso coil length, the endothermic peak becomes weaker, and the T m is generally shifted to a lower temperature for the prepared P3HT 44 ‐ b ‐Piso n copolymers. These phenomena can be explained by the disturbed P3HT interchain packing and the further confined P3HT crystallization while the Piso block with a longer chain length would need more space for stretching …”

The Active Layer Morphology of Organic Solar Cells Probed with Grazing Incidence Scattering Techniques

“…P3HT is among the most studied model systems of conjugated polymers. It is extensively studied as a homopolymer and in blends with electron acceptor materials such as the fullerene derivative [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM) . Today, the active layer material P3HT:PCBM is still among the most frequently studied materials in OPV, although other combinations of conjugated polymers and electron acceptor materials have shown much higher solar cell efficiencies .…”

“…Thus, the crystal structure of P3HT is well‐known and revisited in many studies, which include pure P3HT homopolymer as a reference system . Typically, it is important if the polymer consists of repeat units which are derived from a random isomer of the monomer (regiorandom) or of the same isomer (regioregular).…”

“…Since regiorandom P3HT shows insufficient electric conductivity, regioregular P3HT is used in these investigations . For a sufficiently low polydispersity and high regioregularity P3HT forms lamellar crystals via a π–π‐stacking of the thiophene rings, which stack in a way that the alkane side chains can crystallize . These crystalline regions are separated by amorphous domains.…”

Effective Use of Electrically Insulating Units in Organic Semiconductor Thin Films for High‐Performance Organic Transistors

“…To this end, many EIU/OSC block copolymer systems have been developed for the application in OFETs. Table 1 summarizes characteristics of various OFETs fabricated with EIU/OSC block copolymers . McCullough and co‐workers described the self‐assembly characteristics and resultant electrical properties of the diblock copolymer consisting of regioregular P3HT and poly(methyl acrylate) (P3HT‐ b ‐PMA) .…”